Hey guys
After six month using my Big Weller Flag I feel comfortable to provide the
TB community a solid and trustable update about this new family of RX
antennas.
Results
I started dreaming with 160m back to 1972, motivated my PY1RO,. I got my
first DXCC as PY2FOS / PY2DP from a city lot 30 ft x 60 ft in SPaulo Brazl,
and I took 20 years to work my first 100 DXCC on TB, 1976-1996.
Here in Florida I live on a quite location but still in the suburbs of Ft
Lauderdale and I have one acre lot. I worked 139 DXCC on 160m from 2001 to
Dec 2006 using EWE's, since Dec. 2006 until today I worked 26 new countries
on TB and 33 zones (I mist zone 2 this season) I'm at 165 wkd now on TB (
last one was OX a week ago), whoever with not it in mind I worked 127
countries only in January/February 2007.
Doug NX4D worked 15 new ones since Jan 2007, now he has 222 wkd on TD. Doug
already heard over 269 countries from is 1/3 acre sub-division north of
Orlando using his original Waller Flag.
I heard another 8 countries I was not able to work including DU9, EY8, 4L,
UN, and 9M2.
STOP - IF YOU DON"T DETUNE YOUR TX ANTENNA YOU CAN EXPECT NOT FROM THE WF OR
ANY OTHER RX ANTENNA CLOSE TO IT!
Performance
The diagram you can see on my website represents very well what you can
expect using the WF antenna.
www.n4is.com <http://www.n4is.com/>
When I'm listening weak cw signals, 20 degree makes a huge difference on
copying the station or not. The directivity is very close to + - 35 degree.
The F/S nulls around 30 db helps a lot; I can almost null a S9 signal form
North or S9 QRN from Texas when pointing the antenna to Europe. The F/B
around 30 db for vertical polarized signals also helps a lot. In the morning
if I'm aiming JA, I just can't hear any VK / ZL or South America as well.
Some times the big signal like Jon AA1K, Bill W4ZV or even W8JI can be heard
at noise level when the antenna is at 90 degree from them. The directivity
also helps with local power like noise. I can find the spot with + - 5
degree using the nulls at the side and + - 20 degree using the front lobe.
Noise Ratio
The antenna is very quiet, there is no high angle lobe on the back like the
beverage does the take off angle peaks at 20 degree and drops a lot at 40
degree. The WF is almost 100% vertical and has a very low response for
horizontal polarized signals. One thing noticed the WF is very sensitive to
static rain. When it is raining the antenna is quite useless.
The WF has you close to 12 db RDF, so you can expect 12 db improvement on
weak signals noise ratio, but if you live in a city lot, you still has all
the noise that comes with your location. 12 db gave me a change to try new
ones on 160m. I heard VQ9LA once in 3 years using a EWE, with the WF, I
heard Larry almost every day during the season.
Gain
My initial plan was to increase the size of the WF from Doug original
project to increase the gain 12 db and avoid two preamps. I can use only one
20 db preamp most of the time, whoever when the band is quite I do need a
second preamp, I figured out 30 db gain is a good gain for my Big Weller
Flag, I'm using a 3 section's pre-selector with - 6 db gain between a W7UIV
and a DXE preamp.
So that initial idea did not work well because 30 db is too much for one
unique stage and two 18 / 20 db is more then I need. So, I thing the
original WF design as Doug NX4D built is better, and with one preamp at the
antenna and another one before the radio the 40 db gain is not a problem.
Down side of WF
Having the ability to turn the antenna is huge advantage but during a
contest or a CQ it is a huge handicap at same time, you can't turn it fast
enough to cover 360 degree. A good solution for that was implemented by
PY2DO, Daniel build a frame-less version of the WF between tress, hanging
the loops with a nylon hope at 24 ft high. Daniel has one WF fixed to Europe
and another one fixed to Asia/South Africa. He loves it and he can switch
directions with a single coax switch.
Another down size is rejection of horizontal polarized signals. For that
problem I'm building a second WF horizontal polarized below my actual BWF.
The horizontal pol, WF peaks at 40 degree
New projects
-Horizontal polarized WF
-Two WF side by side at 300ft It has almost 15 db RDF and 54 degree front
lobe,
-Diversity reception using one H and one V WF on each receiver on my IC7800
-Very small WF for 160/80/40m
I would like to invite more Hams to test this new kind of RX antenna and
share they results. I truly believe the WF can be build small as 20 ft by 8
ft using those new low noise devices with 2 db NF and 40 db gain at the
antenna.
Hey guys help me out with those crazy ideas!
Regards
JoseCarlos
N4IS
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